Electromagnetic 3D subsurface imaging with source sparsity for a synthetic object

TL;DR

This paper presents a 3D electromagnetic subsurface imaging method tailored for sparse source data, demonstrating its potential for planetary exploration with minimal payloads.

Contribution

It introduces a 3D inversion approach suitable for sparse sources, specifically designed for astrophysical subsurface imaging with synthetic planetary models.

Findings

Reliable inversion results are achievable with specific data resolution.

The method is promising for lightweight planetary subsurface exploration.

Source sparsity can be effectively managed in 3D electromagnetic imaging.

Abstract

This paper concerns electromagnetic 3D subsurface imaging in connection with sparsity of signal sources. We explored an imaging approach that can be implemented in situations that allow obtaining a large amount of data over a surface or a set of orbits but at the same time require sparsity of the signal sources. Characteristic to such a tomography scenario is that it necessitates the inversion technique to be genuinely three-dimensional: For example, slicing is not possible due to the low number of sources. Here, we primarily focused on astrophysical subsurface exploration purposes. As an example target of our numerical experiments we used a synthetic small planetary object containing three inclusions, e.g. voids, of the size of the wavelength. A tetrahedral arrangement of source positions was used, it being the simplest symmetric point configuration in 3D. Our results suggest that somewhat reliable inversion results can be produced within the present a priori assumptions, if the data can be recorded at a specific resolution. This is valuable early-stage knowledge especially for design of future planetary missions in which the payload needs to be minimized, and potentially also for the development of other lightweight subsurface inspection systems.